The present invention relates generally to the field of imaging systems including one or more peripheral devices, such as systems used in the medical diagnostics field. More particularly, the invention relates to a technique for managing peripheral devices in an imaging system in which certain information and functionalities are stored within circuitry of the peripheral device itself and retrieved as needed by the system.
A wide variety of imaging systems have been developed and are presently in use, particularly in the medical diagnostics field. While very simple imaging systems may comprise self-contained image acquisition and processing components and circuitry, more complex systems include various peripheral devices which may be associated with other system components as needed. In the medical imaging field, for example, systems are typically considered by imaging modality. These modalities may include magnetic resonance imaging (MRI) systems, computed tomography (CT) systems, ultrasound systems, x-ray systems, positron emission tomography (PET) systems, and so forth. Depending upon the physics involved in acquiring and reconstructing useful images, these systems call upon different control and processing circuitry, as well as peripheral devices for data acquisition, processing, storage, and output or viewing.
By way of example, in an MRI system, image data is acquired by imposing magnetic fields on a subject, including a primary magnetic field and a series of gradient fields. The fields define an imaging slice through the subject and encode positions of materials of interest in the selected slice as a function of frequency. After imposition of radio frequency pulses, transverse moments are produced in gyromagnetic material of the subject through the slice, and echo signals from the material can be sensed and processed to identify the intensity of the response at the various locations in the slice. After data processing, an image can be reconstructed based upon the acquired and processed data.
Continuing with the example of an MRI system, various peripheral devices are typically used in the image acquisition, processing, reconstruction, and output of useful images. Depending upon the system design, various types and configurations of RF coils are used to excite the gyromagnetic material, and to capture response signals. In a broad sense, subsystems of the overall imaging system may be considered peripherals, including gradient coils, a primary magnet, a table or support on which a patient is positioned, and so forth. Each of these peripheral devices or subsystems must be properly controlled to reliably produce the desired image data. Similar peripheral devices and subsystems are present in the other modality imaging equipment, particularly in x-ray systems, CT systems, ultrasound systems, and so forth.
Proper coordination of subsystems and peripheral devices in imaging systems is critical to the capture, processing and display of desired images. In particular, many subsystems and peripheral devices must be appropriately calibrated to account for device-to-device variances and tolerances, as well as for similar tolerances within individual devices. Moreover, where alternative devices are employed in a system, such as RF coils in an MRI system, the devices typically have different characteristics which must be taken into account during both the image data acquisition operation and during subsequent data processing.
At present, peripheral devices in medical diagnostic equipment are identified and selected by clinicians and radiologists, and typically identified to the imaging system via an operator input. In the specific example described above, an RF coil in an MRI system would be selected depending upon the anatomy to be imaged and the available imaging protocols of an individual system, and the operator would then identify the coil to the controller. The controller, or memory associated with the controller, may then call upon stored data representative of known or calibrated characteristics of the coil. If the operator improperly identifies the coil, or if the characteristics of the coil are erroneously referenced, appropriate image data will not be collected, or time is lost in identifying or correcting the identification and peripheral data problem.
In addition to the identification and calibration data for imaging system peripherals, various information is typically known relating to manufacturing, servicing, and other historical details of the subsystems and peripherals. This information may be extremely useful in evaluating performance of various peripheral devices, anticipating potential maintenance issues, and correcting or tracing manufacturing or servicing records. At present, this information is generally stored in cross-referenced files of imaging system control circuitry, or, more commonly, in entirely separate manufacturing and service records at diverse locations, including at a hospital or medical institution, at individual service providers, and so forth.
There is a need for an improved technique for managing data relating to imaging system peripherals and subsystems. There is a particular need at present for a technique which may be applied to a wide variety of peripheral devices, permitting more efficient identification of the devices themselves, as well as calibration, service history, and other data which may be of use in the imaging process or in the servicing and maintenance of the system.
The invention provides a technique for managing imaging system peripheral data designed to respond to these needs. The technique may be applied to a wide range of practical applications, but is particularly well suited to complex imaging systems used in the medical diagnostics field. Within that field, the technique has particular promise for managing data in MRI systems, CT systems, x-ray systems, PET systems, and so forth. In a general sense, the technique permits data to be stored within the peripheral device or subsystem itself. This data may include a minimal data set, such as the identity of the peripheral device, or more elaborate data sets, such as calibration information, service history, manufacturing history, usage information, and the like. Moreover, functional data, including programs and subroutines, may be stored within the peripheral device and made executable upon demand. Finally, the circuitry permitting the storage and access to the peripheral device data may include circuitry for encrypting and decrypting information, or for providing limited access to the data, such as by authorized service personnel.
In accordance with one aspect of the technique, memory and communications circuitry is included as an integral part of the peripheral device. Identification data is stored in the device for subsequent access by an imaging system. Upon connection of the peripheral device to the imaging system, the data may be retrieved and an imaging sequence performed based upon the retrieved information. The retrieved information may be cross-referenced to data, such as calibration data or service history data in a memory circuit external to the periphery device. However, where desired, this information may be stored directly in the circuitry of the peripheral device for direct access, loading and use by the external components. Because the information remains resident in the peripheral device, it can be freely accessed, uploaded, downloaded, modified and used whether the peripheral device is employed with the imaging system or apart from the imaging system, such as in a remote servicing location.